VK_KHR_vulkan_memory_model – This extension allows use of the Vulkan Memory Model, which formally defines how to synchronize memory accesses to the same memory locations performed by multiple shader invocations.

VK_KHR_driver_properties - This extension provides a new physical device query which allows retrieving information about the driver implementation, allowing applications to determine which physical device corresponds to which particular vendor’s driver, and which conformance test suite version the driver implementation is compliant with.